Climate Change on Saturn’s Largest Moon
Titan, the largest moon of Saturn, is the only body other than Earth known to have rivers and lakes on its surface, but unlike Earth, these features are composed of hydrocarbons (primarily ethane and methane) eroding into a water ice bedrock. How this surface has evolved to what we observe today is a major question within the planetary sciences, and has profound implications for the moon’s potential habitability. Graduate student Alex Morgan and professor Alan Howard use the geographic distribution of terrain types to decipher the geologic history and climatic evolution of this moon. From their mapping results, they hypothesize that Titan has experienced a relatively brief period in which precipitation was able to affect geomorphic change, possibly triggered by solar brightening or a large impact event. Precipitation is currently declining and retreating towards the poles.
Note the similarities in morphology in the figure: these are same-scale images of water-modified surfaces on Earth (right) and hydrocarbon-modified surfaces on Titan (left). Images from Google Earth and NASA/JPL.